In Situ Electroreorganization of Self-Assembled Perylene Diimide Enables Ultrahigh-Rate and Ultralong-Cycle-Life Sodium Organic Batteries.

Abstract

Morphology optimization of organic electrodes with more exposed redox-active sites and large contact area between active materials and conductive carbon is crucial for higher actual capacity, and improved rate performance, however, is also challenging. In this work, we report a self-assembled perylene diimide disodium salts (PDI-ONa)-based cathode for sodium organic batteries (SOBs) and unveil an in situ electro-induced reorganization process that optimizes the nanostructured morphology and significantly improves the ionic and electronic transport. Experimental and theoretical data suggest that such reorganization is driven by the continuous dissociation/restacking of PDI-ONa during cycling. The resulting reorganized PDI-ONa electrode exhibits excellent rate (136 and 126 mA h g^-1 at 0.2 and 100 A g^-1) and cycling performance (141 mA h g^-1 after 24,000 cycles at 3 A g^-1). Even at -30 °C, it can also perform well (140 mA h g^-1 after 500 cycles at 0.1 A g^-1). Our findings provide a fresh perspective on optimizing organic nanostructured electrodes for high-performance SOBs.